Coconut I completely understand the emotions you are going through. It's very tough because you were hurt so bad. You don't want this to happen again and you want to try and control the environment so that you can't get hurt like that.
I've been there done that.
DDJ is right. There is no way to fully affair proof a marriage.
However I do think you can try and protect your marriage.
To me there is a difference between protecting and controlling.
Controlling would be telling your W she can not have snapchat on her phone
Protecting is processing the emotions and telling her why you would not like her to have snapchat on her phone.
After that the choice is hers and you can only trust her or not

Have y'all had a discussion on how long she was going to give access, etc
I know that's one of the things that happens in my R. Because we didn't really put a "time frame" on it, I just did it whenever I wanted and it became an addiction and she felt like she had zero privacy


M 37 W 30
S 7
Together 10 years
Married 9 years
BD: 12/12/12(W filed same day)
I moved to apartment 1/11/13
W and S moved to MIL 1/11/13
Peicing: 6/3/13
Reconciled: 7/2013
BD2: 4/20/16
still working on it